1. Field of Invention
The present invention relates to a waste heat retrieval system of a vehicle that retrieves waste heat that is exhausted from a vehicle through working fluid and transforms the retrieved heat energy to kinetic energy to improve overall energy efficiency.
2. Description of Related Art
Generally, arts for retrieving energy from gas exhausted from an engine have been developed.
One type of the arts uses a turbo generator that transforms energy of exhaust gas directly to rotation energy to generate electricity, and another type thereof uses a Rankin cycle that generates steam by using heat of exhaust gas and rotates a turbine through the steam. Also, there is an art that uses a thermo element to generate electrical energy.
A separate working fluid is used in the Rankin cycle to retrieve the heat energy from the exhaust gas that is wasted, and one such fluid can be water.
However, the freezing point of water is 0 degrees Celsius, so it is hard to apply the water to the Rankin cycle as a working fluid in various driving conditions of a vehicle.
The information disclosed in this Background section is only for enhancement of understanding of the general background of the invention and should not be taken as an acknowledgement or any form of suggestion that this information forms the prior art already known to a person skilled in the art.